A glossy royal icing is an essential ingredient for sugar cookie decorating. It’s also a basic recipe that any baker should master. This Royal Icing recipe is easily scalable; it’s based on a ratio of 3 parts sugar to 1 part meringue powder. You can multiply this ratio as needed based on the size your cookie batch (3:1 will make enough icing to decorate around a dozen cookies, while 6:2 will make enough icing for around two dozen cookies). We impart extra flavor to our Royal Icing with vanilla and almond extracts, but feel free to experiment with flavors that suit your taste.With only five ingredients, this simple icing comes together quickly (with the help of an electric standing mixer). Although the recipe itself may be straightforward, there are lots of ways to go wrong with royal icing. The most common mistake is adding too much water, which results in an icing that’s too loose to pipe. It’s crucial to add the water slowly and let it fully incorporate before adding more. This recipe calls for 1/2 cup of water, but this amount will likely vary each time you make the icing—instead of sticking closely to the water measurement, focus on achieving the desired texture. It’s also important to sift the powdered sugar to prevent lumps in your icing.For a piping consistency, look for a glossy icing that pulls back in soft peaks from the mixer attachment. For a flooding consistency, look for an icing that falls quickly from the spoon (looser and more liquid than soft peaks, but still able to hold its shape).